Compression spring assembly and method

Abstract

A compression spring assembly can include a compression spring core and a compression spring shell that can be assembled onto the compression spring core. The compression spring core can include a core body with an outer core wall. The compression spring shell can include a shell body having an inner shell wall. The compression spring shell can be supported on the compression spring core such that the inner shell wall extends along at least a portion of the outer core wall. A method of manufacturing a compression spring assembly is also included.

The invention claimed is: 
     
       1. A compression spring assembly comprising:
 a compression spring core including a core body formed from one of cured rubber material and thermoplastic elastomer material, said core body extending longitudinally between opposing first and second core ends and having a longitudinal axis, said core body including a first core end surface, a second core end surface disposed in longitudinally-spaced relation to said first core end surface and an outer core surface; and, 
 a compression spring shell including:
 a first shell body including at least one layer formed from one of cured rubber material and thermoplastic elastomer material, said first shell body extending longitudinally between opposing first shell ends, said first shell body including a first shell end surface, a second shell end surface disposed in longitudinally-spaced relation to said first shell end surface, a first inner shell surface and a first outer shell surface, said first inner shell surface at least partially defining a first shell inner passage extending at least approximately longitudinally through said first shell body; and, 
 a second shell body including at least one layer formed from one of cured rubber material and thermoplastic elastomer material, said second shell body extending longitudinally between opposing second shell ends, said second shell body including a third shell end surface, a fourth shell end surface disposed in longitudinally-spaced relation to said third shell end surface, a second inner shell surface and a second outer shell surface, said second inner shell surface at least partially defining a second shell inner passage extending at least approximately longitudinally through said second shell body; 
 
 said compression spring core and said first and second shell bodies each being cured separately from one another prior to assembly in which said first and second shell bodies are telescoped over and supported on said compression spring core such that said first inner shell surface of said first shell body and said second inner shell surface of said second shell body extend along and in abutting engagement with at least a portion of said outer core surface. 
 
     
     
       2. A compression spring assembly according to  claim 1 , wherein said compression shell spring includes a third shell body including at least one layer formed from one of cured rubber material and thermoplastic elastomer material, said third shell body extending longitudinally between opposing third shell ends, said third shell body including a fifth shell end surface, a sixth shell end surface disposed in longitudinally-spaced relation to said fifth shell end surface, a third inner shell surface and a third outer shell surface, said third inner shell surface at least partially defining a third shell inner passage extending at least approximately longitudinally through said third shell body, said third shell body being supported on said compression spring core such that said third inner shell surface extends along and is in abutting engagement with at least a portion of said outer core surface. 
     
     
       3. A compression spring assembly according to  claim 2 , wherein said first shell body includes first and second reinforcing layers, said second shell body includes third and fourth reinforcing layers and said third shell body includes fifth and sixth reinforcing layers, said first and second reinforcing layers include reinforcing cords disposed in opposing directions at a first bias angle relative to said longitudinal axis, said third and fourth reinforcing layers include reinforcing cords disposed in opposing directions at a second bias angle relative to said longitudinal axis, and said fifth and sixth reinforcing layers include reinforcing cords disposed in opposing directions at a third bias angle relative to said longitudinal axis. 
     
     
       4. A compression spring assembly according to  claim 3 , wherein said first and third shell bodies are disposed in longitudinally-spaced relation to one another along said compression spring core with said second shell body disposed between said first and third shell bodies, and said first and third bias angles are approximately equal to one another such that said first and third shell bodies contribute to approximately equal spring rates along corresponding portions of said compression spring assembly. 
     
     
       5. A compression spring assembly comprising:
 a compression spring core including a core body formed from one of cured rubber material and thermoplastic elastomer material, said core body extending longitudinally between opposing first and second core ends and having a longitudinal axis, said core body including a first core end surface, a second core end surface disposed in longitudinally-spaced relation to said first core end surface, an inner core surface and an outer core surface, said inner core surface at least partially defining a core inner passage extending at least approximately longitudinally through said core body; and, 
 a compression spring shell including:
 a first shell body including at least one layer formed from one of cured rubber material and thermoplastic elastomer material with first and second reinforcing layers at least partially embedded therein, said first shell body extending longitudinally between opposing first shell ends, said first shell body including a first shell end surface, a second shell end surface disposed in longitudinally-spaced relation to said first shell end surface, a first inner shell surface and a first outer shell surface, said first inner shell surface at least partially defining a first shell inner passage extending at least approximately longitudinally through said first shell body, said first and second reinforcing layers including reinforcing cords disposed between said first inner shell surface and said first outer shell surface and oriented in opposing directions at a first bias angle relative to said longitudinal axis; 
 a second shell body including at least one layer formed from one of cured rubber material and thermoplastic elastomer material with third and fourth reinforcing layers at least partially embedded therein, said second shell body extending longitudinally between opposing second shell ends, said second shell body including a third shell end surface, a fourth shell end surface disposed in longitudinally-spaced relation to said third shell end surface, a second inner shell surface and a second outer shell surface, said second inner shell surface at least partially defining a second shell inner passage extending at least approximately longitudinally through said second shell body, said third and fourth reinforcing layers including reinforcing cords disposed between said second inner shell surface and said second outer shell surface and oriented in opposing directions at a second bias angle relative to said longitudinal axis; and, 
 a third shell body including at least one layer formed from one of cured rubber material and thermoplastic elastomer material with fifth and sixth reinforcing layers at least partially embedded therein, said third shell body extending longitudinally between opposing third shell ends, said third shell body including a fifth shell end surface, a sixth shell end surface disposed in longitudinally-spaced relation to said fifth shell end surface, a third inner shell surface and a third outer shell surface, said third inner shell surface at least partially defining a third shell inner passage extending at least approximately longitudinally through said third shell body, said fifth and sixth reinforcing layers including reinforcing cords disposed between said third inner shell surface and said third outer shell surface and oriented in opposing directions at a third bias angle relative to said longitudinal axis; 
 
 said first, second and third shell bodies of said compression spring shell being supported on said compression spring core such that said first inner shell surface of said first shell body, said second inner shell surface of said second shell body and said third inner shell surface of said third shell body extend along and in abutting engagement with at least a portion of said outer core surface with at least one of said first, second and third bias angles being different from one other of said first, second and third bias angles such that said first, second and third shell bodies contribute to two or more different spring rates along corresponding portions of said compression spring assembly. 
 
     
     
       6. A compression spring assembly comprising:
 a compression spring core at least partially formed from one of cured rubber material and thermoplastic elastomer, said compression spring core including a core body extending longitudinally between opposing first and second core ends and having a longitudinal axis, said core body including a first core end surface, a second core end surface disposed in longitudinally-spaced relation to said first core end surface; and, 
 a compression spring shell formed separately from said compression spring core and at least partially from one of cured rubber material and thermoplastic elastomer material, said compression spring shell including a shell body and a plurality of reinforcing layers embedded therein, said compression spring shell extending longitudinally between opposing first and second shell ends, said shell body including a first shell end surface, a second shell end surface disposed in longitudinally-spaced relation to said first shell end surface, an inner shell surface and an outer shell surface, said inner shell surface at least partially defining a shell inner passage extending at least approximately longitudinally through said shell body, said plurality reinforcing layers including reinforcing cords disposed between said inner and outer shell surfaces; 
 said compression spring shell supported on said compression spring core such that said inner shell surface extends coextensively along and in facing relation with at least a portion of said outer core surface. 
 
     
     
       7. A compression spring assembly according to  claim 6 , wherein said compression spring shell is removably supported on said compression spring core with said outer core surface and said inner shell surface frictionally interengaging one another to at least partially retain said compression spring shell on said compression spring core. 
     
     
       8. A compression spring assembly according to  claim 6 , wherein said compression spring shell is fixedly attached to said compression spring core by an adhesive substance disposed between said outer core surface and said inner shell surface. 
     
     
       9. A compression spring assembly according to  claim 6 , wherein said core body includes an inner core surface at least partially defining a core inner passage extending at least approximately longitudinally through said core body. 
     
     
       10. A compression spring assembly according to  claim 6 , wherein compression spring core has a core height defined between said first and second core end surfaces, and said compression spring shell has a shell height defined between said first and second shell end surfaces that is less than said core height of said compression spring core. 
     
     
       11. A compression spring assembly according to  claim 6 , wherein said compression spring shell includes an inner layer that at least partially defines said inner shell surface. 
     
     
       12. A compression spring assembly according to  claim 6 , wherein said plurality of reinforcing layers include a first reinforcing layer and a second reinforcing layer, said first reinforcing layer including a first plurality of reinforcing cords disposed at a first bias angle relative to said longitudinal axis, and said second reinforcing layer including a second plurality of reinforcing cords disposed at a second bias angle relative to said longitudinal axis. 
     
     
       13. A compression spring assembly according to  claim 12 , wherein said first and second pluralities of reinforcing cords are disposed in opposing orientations relative to one another with said first and second bias angles being at least approximately equal to one another in opposing directions. 
     
     
       14. A compression spring assembly according to  claim 6 , wherein said compression spring shell includes an outer layer that at least partially defines said outer shell surface. 
     
     
       15. A compression spring assembly according to  claim 6 , wherein said core body includes an annular groove having a bottom wall portion and an open end opposite said bottom wall portion, said annular groove extending into said core body from along one of said first and second core end surfaces such that said open end is formed along said one of said first and second core end surfaces. 
     
     
       16. A compression spring assembly according to  claim 6 , wherein said core body includes a plurality of core outer passages extending at least partially into said core body in circumferentially spaced relation to one another about said longitudinal axis. 
     
     
       17. A compression spring assembly according to  claim 16 , wherein at least one of said plurality of core outer passage extends at least approximately longitudinally through said core body. 
     
     
       18. A compression spring assembly according to  claim 16 , wherein said plurality of core outer passages are approximately evenly spaced from one another about said longitudinal axis. 
     
     
       19. A compression spring assembly according to  claim 6 , wherein said core body includes an annular shoulder wall projecting radially-outwardly beyond said outer core surface and at least partially defining an outmost peripheral extent of said core body. 
     
     
       20. A compression spring assembly according to  claim 19 , wherein said first shell end of said compression spring shell is disposed adjacent said annular shoulder wall of said core body.